Recording and reproducing apparatus

1. A recording and reproducing apparatus comprising: a light source for emitting a light beam; a spatial modulating part for modulating the light beam to create information light, using spatial information associated with page data A to be recorded on a holographic recording medium; an optical-path changing part for changing an optical path of the information light created by the spatial modulating part; a light detecting part for receiving the information light having the optical path changed by the optical-path changing part; and a diagnosis part for inspecting operations of recording and reproducing components including the spatial modulating part and the light detecting part, using the page data A and page data B obtained from the information light received by the light detecting part.

2. The recording and reproducing apparatus according to claim 1 , wherein the optical-path changing part is a beam splitter for turning the optical path of the information light created by the spatial modulating part toward the light detecting part.

3. The recording and reproducing apparatus according to claim 2 , wherein the beam splitter is movably placed so as to allow the information light to travel toward a holographic recording medium during recording of page data on the medium and, so as to allow the information light to travel toward the light detecting part during inspection of the operations by the diagnosis part.

4. The recording and reproducing apparatus according to claim 1 , wherein an optical lens for directing the information light to a predetermined position on the medium is provided on the optical path of the information light between the spatial modulating part and the holographic recording medium, and the optical-path changing part is provided between the spatial modulating part and the optical lens, so that the information light is received by the light detecting part without through the optical lens.

5. The recording and reproducing apparatus according to claim 4 , wherein the optical-path changing part is constituted by a mirror and a beam splitter for passing the information light created by the spatial modulating part therethrough toward the holographic recording medium while turning the optical path of the information light reflected by the mirror toward the light detecting part, and the mirror is placed between the beam splitter and the optical lens.

6. The recording and reproducing apparatus according to claim 1 , wherein an optical lens for directing the information light to a predetermined position on the medium is provided on the optical path of the information light between the spatial modulating part and the holographic recording medium, and the optical-path changing part is provided between the optical lens and the medium, so that the information light passed through the optical lens is received by the light detecting part after the optical path thereof is changed by the optical-path changing part.

7. The recording and reproducing apparatus according to claim 6 , wherein the optical-path changing part is a movable mirror.

8. The recording and reproducing apparatus according to claim 1 , wherein the optical-path changing part is provided on a surface of the holographic recording medium, the optical-path changing part reflects the information light created by the spatial modulating part, and the reflected information light is received by the light detecting part.

9. The recording and reproducing apparatus according to claim 8 , wherein the optical-path changing part is a mirror.

10. The recording and reproducing apparatus according to claim 1 , wherein the optical-path changing part is a light transmitting part provided in the holographic recording medium, and the information light created by the spatial modulating part and directed to the light transmitting part is passed through the medium and then received by the light detecting part.

11. The recording and reproducing apparatus according to claim 1 , wherein the diagnosis part includes a storing part which prestores page data A consisting of known information, a comparing part for comparing the page data A with page data B obtained from the information light received by the light detecting part, and a defect detecting part for detecting whether or not there is a defect in the recording and reproducing components, on the basis of the result of the comparison.

12. The recording and reproducing apparatus according to claim 11 , further comprising: a result outputting part for outputting the result of detection by the defect detecting part.

13. The recording and reproducing apparatus according to claim 1 , further comprising: a component adjusting part which, when the diagnosis part determines that there is a malfunction of the operation of any of the recording and reproducing components, adjusts the component determined to have a malfunction.

14. The recording and reproducing apparatus according to claim 13 , wherein when the component determined to have a malfunction is the spatial modulating part or the light detecting part, the diagnosis part identifies the defective positions and the component adjusting part executes a replacing process for creating spatial information in which data to be recorded into the identified defective positions is shifted to a predetermined replacement region.

15. The recording and reproducing apparatus according to claim 1 , wherein the diagnosis part starts the inspection of the operations of the recording and reproducing components in the event of any of when it is detected that the power is turned on, when it is detected that a portable holographic recording medium has been inserted, when a recording request or a reproduction request is detected, every time when a constant time interval has elapsed at a state where the recording and reproducing operation is not performed, when the number of times that a malfunction of the recording operation or the reproducing operation is detected exceeds a predetermined number, when the temperature within the apparatus rises to a set temperature or more, when a shock sensor mounted to the inside of the apparatus detects a shock of a predetermined value or more and when a command for execution of a diagnosis process is input.

16. The recording and reproducing apparatus according to claim 1 , wherein the light beam emitted from the light source is a ring-shaped light beam consisting of a central first light beam and a second light beam formed around the first light beam, the first light beam is information light associated with page data to be written into the holographic recording medium, the second light beam is reference light for reading out page data recorded on the holographic recording medium, and the information light and the reference light are both incident on the spatial modulating part.